Field of Invention
This invention generally relates to an image correction design system and method for an oral and maxillofacial surgery, especially to an image correction design system and method for a dental, orthognathic and facial plastic surgery.
Description of Related Arts
Orthognathic surgery is surgery designed to correct conditions of the jaw and face related to structure, growth, sleep apnea, TMJ disorders, malocclusion problems owing to skeletal disharmonies, or other orthodontic problems that cannot be easily treated with braces. This surgery is also used to treat a patient with congenital cleft palate.
During an orthognathic surgery, bone of a patient is cut and adjusted by a physician, and then a bone plate and bone nails are joined to the skeleton and performing shaping. Typically as the orthognathic surgery is performed by a physician, a clinic file of X-ray machine or computerized tomography (CT) scan of a patient is needed to confirm a predetermined operation site, and a dental impression and correction for the surgery portion are performed according to the experience of the physician. In addition, in order to facilitate the fixation of the jaws or skeleton, a physician usually needs to use a medical metal bone plate, screws, bone nails, stainless steel wire and other materials for fixing and shaping the structure of the patient's jaws and face.
However, the common medical photographic equipment used in an oral and maxillofacial surgery cannot provide a correct image data accurately for simulation assessment before surgery or healing over confirmation after surgery to a physician. Generally, an orthognathic surgery is performed by a physician only according to the photographs taken by the current situation and the experience accumulated by the physician for years. The photographs are not true to the original that may cause misjudgment of the surgery portion and a prolongation of surgery time. Also, it fails to provide a physician with a comparing basis for tracking healing and preoperative assessment in real time during corrective treatment after surgery. In addition, it is possible to cause disadvantages of malocclusion that a patient fails to have a correct occlusion or has an excessive occlusion. Therefore, the experience and skills of physicians are often important factors in determining the success or failure of these operations.
Taiwan Patent No. 1367745 entitled “3D planning and prediction method for optimizing facial skeleton symmetry in orthognathic surgery” discloses a way of the best global positioning evaluation for dental model navigation in surgical planning using the best symmetry plane method. Base on the precision of coordinate relationships among the image model, tracking system, and dental cast, osteotomy prediction for jaw correction surgery can be achieved by assessing the symmetry degree in both oral and maxillofacial regions. Cephalometric analysis and evaluation of orthognathic surgery are elevated from two dimensions to three dimensions in order to compromise both oral functional restoration and aesthetics requirements. However, the planning and prediction method for optimizing facial skeleton symmetry fails to solve the problem that image is affected by noise and other interference factors, so that the converted file is not true to the original or the image is vague to cause misjudgment, and thus it cannot provide a correct image data accurately for simulation assessment before surgery or healing over confirmation after surgery by a physician.
Taiwan Patent No. 1397402 entitled “an integration method of dental implant positioning and implant guide planning” discloses an integrated method of implant position planning and drilling guide generation for dental implant. The method is based on patient's jaw models reconstructed from CT images and combines with his own dynamic occlusion surface. The optimal entry point of the implant can either be determined by patient's occlusal surface or the moment of inertia of the jawbone in order to obtain a possible position of the implant automatically. The planning process takes into account several crucial lengths, in terms of safety distances, between the skull boundary, the nerve, and the implants, and could be fabricated by rapid prototyping machine. The design of the guide template solves the undercut interference when mount the guide plate on teeth, and also take into consideration mouth opening distance and clinical issues in order to build high precision and accuracy drill guide plate using in dental implant. However, the above method still has accuracy problem of the CT images and patient's jaw models. It's possible to cause disadvantages of malocclusion that a patient fails to have a correct occlusion or has an excessive occlusion.
Taiwan Patent No. 1385606 entitled “method of locating and correcting a solid model of teeth and jaws and fixture thereof” discloses a method of locating and correcting a solid model of teeth and jaws, comprising a selecting step, a scanning step, a manufacturing step, a placing step, a positioning step and a correcting step. A teeth and jaws solid model is used as a standard model and a target tooth is selected to make a fixture according to the preceding steps, and the fixture is arranged on the corresponding teeth of a model to be corrected, and a positioning system, a positioning plate and a handheld positioning machine with a positioning mark are used to perform positioning and correction. The positioning and correction can be performed for every tooth respectively by the above steps. However, the above method cannot scan the skeleton image accurately and provide positioning, and thus it cannot provide a correct image data accurately for simulation assessment before surgery or healing over confirmation after surgery by a physician.
In summary, it is necessary to propose an image correction design system and method for an oral and maxillofacial surgery that can be applied to a dental, orthognathic and facial plastic surgery, and can accurately provide a correct image data to a physician to do a simulated preoperative assessment or postoperative healing confirmation to shorten the time of surgery and improve the success rate of these operations.